MDM4 and Familial prostate cancer: To investigate the role of p53 pathway in prostate cancer progression, we analyzed the prostate cancer genomic datasets in TCGA using cBioPortal. Our analysis of a CRPC dataset (Trento/Cornell/Broad 2016) revealed that MDMX is amplified in 32% of CRPC patients, compared to MDM2, which is amplified in 25% of CRPC patients (Figure 1A).